This invention relates generally to enhanced television broadcasts which are also sometimes known as interactive television broadcasts.
In enhanced television or interactive broadcasts, a television program may be broadcast together with certain enhancements. The enhancements may in some cases be related to the television program and may be accessed through hypertext markup language documents. These documents may be transmitted with the television program or may be accessible independently from the program, for example over the Internet. Thus, in many cases, the enhancements add to the information that viewers can obtain about a particular program.
Conventionally, the enhancements relate to a particular television program. At the end of that program therefore, it may be desirable to terminate the availability of the enhancement. Otherwise, viewers may become confused because enhancements associated with one program may then be accessed during subsequent programs.
One applicable specification, the ATVEF Specification, suggests that script or other scripting mechanisms be utilized to terminate the enhancements at the end of a television program. See Advanced Television Enhancement Forum (ATVEF) Enhanced Content Specification, v. 1.1r26 (1998-99) (hereinafter the “ATVEF Specification”). However, the ATVEF Specification provides no particular technique to do so. Using scripts or scripting mechanisms may add complexity.
In addition, problems may arise with respect to terminating enhancements automatically at the end of the program. For example, a viewer may be viewing an enhancement associated with one program and may not care about the ensuing program. Instead, the viewer may wish to continue to view enhancements related to a previous program regardless of the ensuing program. Therefore, adopting the approach suggested in the ATVEF Specification may be annoying for some viewers.
Thus, there is a need for better ways to ensure that enhancements associated with one program are not inadvertently made available during an ensuing program.